io Input/Output

GPIO

In this window, each individual GPIO (General Purpose Input/Output) behavior can be configured:

../../_images/gpio.png

GPIO panel

  1. Signal: Pin ID as described in Hardware installation - Pinout section of the CEX Hardware Manual.

  2. GPIOId: GPIO ID of the microcontroller.

  3. IO: Define GPIO as an input or output.

  4. Pull-up: Enable or disable the pull-up resistance.

  5. Function: Mux 0/GPIO: GPIO, Mux 1: PWM, Mux 2 or Mux 3. These are the different functionalities that the GPIO can have, depending on the multiplexer.

    Note

    When users set Function to “Mux 1”, it indicates that the corresponding pin is disabled as GPIO and enabled as PWM. Consequently, the Enable checkbox in the PWM menu for that pin should be activated automatically.

    Warning

    Check that the corresponding Enable checkbox in the PWM menu is changed.

  6. Qsel: This is the “input qualification”, it is used to control how the value of a GPIO is evaluated. The available options are:

    • Sync: The value is taken as the time it is checked (synchronously). This is the default mode of all GPIO pins.

    • 3 Samples: The value is checked 3 times and the value is only changed when the 3 times are the same.

    • 6 Samples: Same as 3 samples, but checking 6 times instead of 3.

    • ASync: No checks are performed. It is used when it is not used as GPIO.

PWM

In this panel each PWM can be configured:

../../_images/pwm.png

PWM panel

Note

PWMs in CEX work in normalized mode, so when the input value is 0 the output value will be the minimum configured, and when the input value is 4095 (12 bits all with ones), the output will be the maximum configured. This approach allows usage of the maximum resolution for the commanded value.

The configuration parameters are:

  1. Enable: Defines if the PWM is enabled or not.

    Note

    This checkbox disables the pin as GPIO and enables it as PWM. Hence, in the GPIO menu the “Function” parameter shall change to “Mux 1”.

  2. Sub id: Identifies the sub-id of the PWM and, according to this value, determines the command to be used, using one type of CAN message or another.

  3. Frequency: PWM output frequency. This determines the period of the pulses sent by the CEX.

  4. Timeout: If a PWM message is not received in less than this time, the PWM will output the start value.

  5. Start value: Value used before any PWM message arrives and on timeout.

  6. Pulse source ID: PWM input ID [0,3], defined in the Digital Input panel.

  7. Active High: Polarity high or low (high if enabled).

  8. Mode: The avilable options are Time and Duty cycle.

    • Time: The values indicated in Min and Max parameters are expressed in time units.

    • Duty cycle: This option is a a different way of indicating the pulse width. Now the value indicated in Min and Max parameters is a percentage which corresponds to the relation between the pulse width over the total period of the sent signal.

      So a 100% duty cycle will correspond to a signal with a constant value of 1, while a 0% duty cycle implies a constant signal with value 0. Between this two extremes, the pulse width can vary as in the examples shown in the following figure.

      ../../_images/duty_cycle.png

      Duty cycle

      Note

      Duty cycle percentages can be expressed in percent and per unit.

  9. Min: This parameter is the pulse width value that will make the servo/actuator go to its lowest position.

    It will be the output when the PWM message specifies 0.

  10. Max: This parameter is the pulse width value that will make the servo/actuator go to its highest position.

    It will be the output when the PWM message specifies 4095.

An example of reading PWM can be found in Commanding/Reading PWMs - Integration examples section.

I/O Setup

In this panel the user can establish the relationship between a determined signal with a I/O port. This allows users to configure serial inputs and outputs: external sensors, custom messages, etc.

../../_images/io_setup.png

I/O Setup panel

  • Priority: Connections between I/O ports can be marked with high priority with this checkbox. If enabled, they will run at high frequency: 1000 Hz.

  • Producer: Functions for creating and sending messages.

  • Consumer: Functions for receiving and parsing messages

Firstly, users have to configure the Producer selecting the I/O port or information to use. Later, users have to configure the Consumer by clicking on an element, a new window will be displayed to select an item. The relationship between them can be unidirectional (Bind \(\rightarrow\)) or bidirectional (Bind Bidirectional \(\leftrightarrow\)), the last enables a port to receive or send information.

../../_images/io_setup_consumer.png

I/O Setup consumer options

The following I/O ports are available:

Field

Description

UART-A / RS232-A

Serial Port 232

UART-B / RS232-B

Serial Port 232

UART-C / RS485

Serial Port 485

Commgr port

COM Manager ports send and receive VCP messages. VCP is the protocol used by Veronte products to communicate.

For more information on this, read the VCP user manual

Tunnel

Creates a bidirectional brigde between two devices, see Tunnel

Custom message producer/consumer

This allows user to send/receive a serial custom message, see Custom message

Y splitter producer/consumer

Used to split a signal into 2

CAN to serial / Serial to CAN

Serial to CAN sends serial streams via CAN Bus / CAN to serial undoes the transformation ‘Serial to CAN’

CAN wrapper for serial transmission / Serial CAN unwrapper

CAN wrapper sends CAN streams over a serial Bus / Serial CAN unwrapper undoes this transformation

Tribunus ESC

Reads telemetry data from the Tribunus ESCs by connecting it to one of the serial ports

Lift - MCU

Created for communication with a Lift MCU

JETI box

Simulates a Jetibox to read telemetry from legacy Jeti devices, see JETI box

JETI telemetry

Reads telemetry from Jeti devices

More information about some elements can be found in the following sections.

Tunnel

It is possible to configure a Tunnel which is a bidirectional bridge between units that communicate to each other sharing information about an external device connected to the Serial or Digital port.

Let’s consider the following image.

../../_images/tunnel.png

Tunnel configuration

In the image above there is a device connected to the UART-A/RS232-A (Producer) and there is a Tunnel (Consumer) which sends that information to all units on the network (Broadcast). On the other hand, another Veronte device has to be configured to receive the signal sent by another device. In that case the Producer will be Tunnel and Consumer will be the port or destination tunnel where the device is connected.

The option available when configuring Tunnel as Consumer are:

  • Veronte ID: Select the address that will receive the information.

    • App 2: Veronte applications address.

    • Broadcast: All units on the network. Select this option for a generic configuration.

    • CEX2 XXXXX: Address of a specific unit, it can be a CEX, a 1x, a 4x, etc.

  • Parser: The user can choose protocol to parse message data. The options available are:

    • No protocol

    • RTCM3

    • CANserial

  • Destination tunnel: Number of port is used to avoid mistakes and identify a Tunnel when using more than one, Tunnel 1, 2 and 3 are available.

  • Time between messages.

  • Bytes to send: Sets the message size to send.

When configuring Tunnel as Producer (i.e. on the unit that receives the information), no configuration is required. It is only necessary to connect it to a Consumer, usually to a serial port.

Custom Messages

Warning

  • CEX has a serial limitation shared with all Custom Messages:

    • Maximum number of vectors (fieldset): 100

    • Maximum number of fields: 1000

  • Each Custom message consumer has a limit of 32 fields.

It is possible to configure the messages sent/received through the serial port and its conversion to system variables by selecting the option Custom message producer/consumer and configuring the I/O port.

../../_images/serial_custom_message.png

Serial Custom Messages

In the image above can be seen two possible configurations using a Custom Message. The ‘red’ one is configured to receive a determined message from Tunnel 1 and the ‘green’ is used to send a Custom Message through a UART-C/RS485 serial port. It is also possible to use the same Custom Message for both tasks if the bidirectional relationship is selected (the arrow indicates this, \(\leftrightarrow\)).

To configure a Custom message, the user must follow the next steps:

  1. Press the configuration button ( gears icon) and another window will be displayed.

    In this window press the “+” icon to add a custom message.

../../_images/custom_message.png

Serial Custom Message configuration

  1. When it is already added, the following options are available to configure a custom message:

    ../../_images/producer_message.png

    Custom Message producer configuration

    ../../_images/consumer_message.png

    Custom Message consumer configuration

    • Endianness: Depending on the order in which the device issue the message, it is possible to select:

      • Big endian: Set the value from left to right.

      • Little endian: Set the value from right to left.

      • Mixed endian: Some devices use this format. If users need to configure it, please contact the support team (create a ticket in the customer’s Joint Collaboration Framework; for more information, see Tickets section of the JCF manual).

    • Period/Time out: This option has a dual role depending on if it is used to transmit or receive data.

      • Period - Producer: It is the inverse of the send frequency.

      • Time out - Consumer: This is the threshold time between receptions to consider that the message is not being received correctly.

    • Delay/Time to Idle: This option has a dual role depending on if it is used to transmit or receive data.

      • Delay - Producer: It is a delay applied before sending the message. This serves to send messages with the same period without overloading the Serial bus.

      • Time to Idle - Consumer: This is the time CEX waits before discarding partially parsed bytes.

    • Bit ID: This option is only available when a message is configured as Consumer. The user bit selected in Bit ID box will be true if the message is being received correctly.

    Warning

    Pay attention that the user bit selected in Bit ID is not in use for another task.

  2. To create the structure of the message, click on the edit message button ( edit_list icon) and then press the “+” icon to add fields to it. The following type of messages are available to configure a structure: Variable, Checksum, Matcher, Skip, Parse ASCII and Position.

    The configuration of each structure is covered in Custom Messages section of the 1x PDI Builder manual.

Warning

Before configuring any message, user has to know the structure it has to have according to the device that is connected to the port. Each device may have a different message structure when it sends or receives information.

JETI box

JETIBOX is a universal communication terminal which can be used with any JETI products.

JETIBOX operates as a two-way terminal, showing all data stored in the JETIBOX Compatible product. With the use of four buttons, the user can browse the menu and set the selected values to take advantage of the full capability of JETIBOX Compatible products.

../../_images/io_setup_jetibox_device.png

JETI box device

To simulate it, it is necessary to link the specific JETI box consumer to a serial port:

../../_images/io_setup_jetibox1.png

JETI box Consumer

Then, the sequence to retrieve the data shall be configured by clicking on the configuration button ( gears icon):

  • To add a Custom Message, just clik on the “+” icon:

    ../../_images/io_setup_jetibox2.png

    JETI box Configuration

    The following parameters can be configured in this pop-up window:

    • Endianness: Depending on the order in which the device issue the message, it is possible to select:

      • Big endian: Set the value from left to right.

      • Little endian: Set the value from right to left.

      • Mixed endian: Some devices use this format. If users need to configure it, please contact the support team (create a ticket in the customer’s Joint Collaboration Framework; for more information, see Tickets section of the JCF manual).

    • Command: Here the user can select between Jeti box Left, Jeti box Down, Jeti box Up, Jeti box Right or Jeti box Nop. These correspond to the four buttons on the physical JETIBOX (see image above), except the Jeti box Nop that is only for simulating a “wait”.

For example, to read the Actual Voltage of a Jeti MasterSpin 220 the Consumer must be configured with a series of custom messages (use Big endian in all messages).

../../_images/io_setup_jetibox_custom_message_all.png

JETI box example

Below is a small example with the configuration of one of these messages, the full example can be found in Jetibox - Integration examples section.

  1. Expected text: “CONTROLLER TYPE MasterSpin 220~”

    • Command: Jeti Box Down

      • Matcher(32) “CONT” 0x434F4E54 (1129270868)

      • Skip(24*8) 192

      • Matcher(32) “220~” 0x3232307E (842150014)

../../_images/io_setup_jetibox_custom_message.png

JETI box custom message example

CAN I/O

Warning

Remember that for the reception of CAN messages, Mailboxes need to be configured accordingly.

A CAN (Controller Area Network) Bus is a robust standard communication protocol for vehicles widely used in the aviation sector. CEX is fitted with two CAN buses that can be configured independently.

The structure of a CAN message can be seen in the following image:

../../_images/can_structure.png

CAN message structure

Only the ID is introduced in the system, the rest of the message layout is already coded. The data field is the one build by the user to send, and parsed when received.

For more information on the CAN Bus protocol, see CAN Bus protocol section of the CEX Software manual.

The baud rate of both CAN buses can be configured in the CAN Setup panel.

Configuration

This menu allows the configuration of the CAN inputs and outputs.

../../_images/can_io_config.png

CAN configuration panel

In this menu, the user can find the same ‘columns’ (Priority, Producer and Consumer) as in the I/O Setup panel.

Warning

In CAN, while the specified period is not guaranteed in the Low state, in the High state it is.

However, only those messages that are critical for external devices should be set as high priority, as this may disrupt the proper functioning of CEX.

On the one hand, CEX has the producers shown below:

  • Application Processor: Sends a specific set of information, the “status message”. This message is composed as: version (major, minor and revision), address (serial number), system bit error, system power up bit error, PDI bit error, memory allocation bit, fily system bit error, CAN A bit error, CAN B bit error, arbiter enabled and arbiter status.

  • CAN Input Filter: CAN input filters. Those CAN messages received in one filter can no longer be received in subsequent filters. The following parameters need to be configured by clicking on the gears icon:

    ../../_images/can_io_can_input_filter.png

    CAN Input Filter configuration

    • Port: It is required to configure the CAN bus from which it listens, the user can choose between CAN A, CAN B or BOTH.

    • Id: CAN Id must be set and it is used to identify messages. The value set has to be decimal format.

    • Mask: A CAN Id mask can be set to filter messages. The mask marks which bits of the message id (in binary) are matched.

      For example, to admit standard Ids (11 bits) from 8 to 11 (100 to 111 in binary) the user should set the mask to binary 11111111100, that is 2044 in decimal.

      Warning

      Make sure that mask is set properly to be able to receive the desired CAN messages.

      The mask should be 11 bits for Standard frame format and 29 bits for Extended frame format.

      More information about this can be found in How to calculate a mask - FAQ section of this manual.

    • Filter type: The options available are Standard (frame format with a 11-bit identifier), Extended (frame format with a 29-bit identifier) and Both.

  • CAN unwrapper: This undoes the ‘CAN serial wrapper’ action, it has to be connected to I/O Setup consumer (Serial CAN unwrapper).

  • Serial to CAN: Serial messages via CAN output, it has to be connected to I/O Setup consumer. It can be configured in the configuration button ( gears icon), a pop-up window will appear:

    ../../_images/can_io_serial_can.png

    Serial to CAN configuration

    • Id: CAN Id must be set and it is used to identify messages. The value set has to be decimal format.

    • Extended: If enabled, the frame format will be this, ‘Extended’, i.e. with a 29-bit identifier. Otherwise, the frame format ‘Standard’ (11-bit identifier) is set by default.

    • Time out: This is the threshold time between receptions to consider that it is not being received correctly.

  • CAN Custom Producer Telemetry: Telemetry messages sent via CAN (such as CAN custom messages on Veronte Autopilot 1x). They are configured in the next section, see CAN Telemetry.

On the other hand, the consumers are the following:

  • Application Processor: Receives a specific set of information sent by Veronte Autopilot 1x or Arbiter.

  • CAN Output Filter: CAN output filters. The user can choose between CAN A, CAN B or BOTH in the configuration button ( gears icon).

    ../../_images/can_io_can_output_filter.png

    CAN Output Filter configuration

  • CAN serial wrapper: CAN messages via serial output, it has to be connected to I/O Setup producer (CAN wrapper for serial transmission).

  • CAN GPIO consumer: CAN messages from 1x autopilot for GPIO inputs. An example of how to implement it can be found in GPIO Command - Integration examples section.

  • CAN to Serial: This undoes the ‘Serial to CAN’ action, it has to be connected to I/O Setup producer.

  • CAN Custom Consumer Telemetry: Telemetry messages received via CAN (such as CAN custom messages on Veronte Autopilot 1x). They are configured in the next section, see CAN Telemetry.

CAN Telemetry

In the CAN Telemetry tabs (there are 3 available), the user chooses the telemetry to be sent/received via the CAN buses. The following elements can be configured:

  • TX Ini: Used to configure transmitted messages that are only sent once at the beginning of the operation (sent when CEX boots up). They can be used to initialize some devices.

  • TX: Used to configure transmitted messages.

  • RX: Used to configure the reception messages (where they are stored).

Warning

  • The maximum capacity of a CAN message is 64 bits (8 bytes), so to send more information it must be divided into several messages.

  • CEX has a CAN limitation of 40 TX Ini messages per Custom, 40 TX messages per Custom and 80 RX messages per Custom.

    In addition, there is a limit shared with all Customs:

    • Maximum number of vectors (fieldset): 160

    • Maximum number of fields: 1280

../../_images/can_io_telemetry.png

CAN Telemetry panel

Since this panel works in a similar way to the CAN Custom Message configuration in the 1x PDI Builder software, the explanation to configure the telemetry messages via CAN can be found in the Custom Messages - Input/Output section of the 1x PDI Builder user manual.

An example of the sending of CAN telemetry messages can be found in the CAN communication - Integration examples section.

Digital Input

CEX digital signal inputs can be used to measure pulse count, pulse widths and PPM signals from a RC radio. Each source shall be connected to the desired consumer to allow measurements.

../../_images/digital_input1.png

Digital Input panel

In this menu, the user can find the same ‘columns’ (Producer and Consumer) as in the I/O Setup panel.

The process to configure a device can be done as follows:

  1. Select and configure a Producer. There are 4 possible producers: CAP 1 - 4.

    Press on the configuration button ( gears icon) and a new pop-up window will show.

    ../../_images/digital_input2.png

    Digital Input - Producer

    In the pop-up window, users can check:

    • That this producer is enabled.

    • Which pin this CAP is associated to and, therefore, to which device is connected. They are associated in this way: CAP 1 with I/O1, CAP 2 with I/O2, CAP 3 with I/O3 and CAP 4 with I/O4.

    • How pulses are read and transformed into a digital signal (how they are processed). That can be configured with the Edge detection option.

      By clicking on the drop-down menu, the following options can be selected:

      ../../_images/digital_input_edge.png

      Digital Input - Edge detection options

      • First rising edge: With this option, when the rise of the pulse is detected, the data will start to be stored. Recommended when consumer is PPM or Pulse.

      • First falling edge: With this option, when the fall of the pulse is detected, the data will start to be stored.

Note

By clicking on the marked arrows, it can also be configured as desired, getting another scheme.

../../_images/click_arrows.png

  1. Click on the Bind button to select the type of Consumer, it is possible to choose among a PPM 0 (Stick PPM), RPM 1-4 or Pulse 1-4.

    ../../_images/digital_input_consumer.png

    Digital Input - Consumer

    • PPM 0 selected: PPM is configured in the Stick panel.

    • RPM 1-4 selected: The variables in which the information read here is stored are ‘RPM 1-4’. For more information on the configuration of RPM, see the RPM section.

    • Pulse 1-4 selected: The variables in which the information read here is stored are ‘Captured pulse 1-4’. It is possible to configure it cliking on the configuration button ( gears icon):

      ../../_images/digital_input_pulse.png

      Digital Input - Pulse

      In the pop-up window, users will find the following options for configuration:

      • Mode:

        • Positive pulse duration: The period of the pulse is obtained. It takes the time in ‘High’ state.

        • Negative pulse duration: The period of the pulse is obtained. It takes the time in ‘Low’ state.

          ../../_images/digital_input_positive_negative.png

          Positive/Negative pulse duration

        • Positive duty cycle: The duty cycle of the pulse is obtained. It takes the time in ‘High’ state.

        • Negative duty cycle: The duty cycle of the pulse is obtained. It takes the time in ‘Low’ state.

          ../../_images/duty_cycle.png

          Positive/Negative duty cycle

      • Time out: This defines the time to consider that no signal is received.

      • Function: Here the user can customise a function to handle the values. Normally, a function is set with the points [0,0] and [1,1], so no transformation is applied, input = output. However, the user can configure it as desired.

Example

Let’s imagine that First rising edge has been selected as the wrap option in Producer and the pulse that CEX has to read is a square signal with a period of 2 seconds and a duty cycle of 25% (see image below).

../../_images/digital_input_signal.png

Signal generated

On the other hand, if Positive pulse duration is selected as Consumer and it is configured as in the previous image (Digital Input - Pulse), the value obtained in the variable Captured pulse (Captured pulse 1 in the following example) will be 0.50s, this is because it is the period of the “Positive pulse” of that pulse.

However, if Positive duty cycle is selected as Consumer, the value obtained in the variable Captured pulse (Captured pulse 2 in the following example) will be 0.25, this is because it is the positive duty cycle of that pulse.

../../_images/digital_input_signal_vops.png

Digital Input example

SCI

CEX can use up to three serial peripherals (SCI A, SCI B and SCI C). Serial ports A, B and C parameters can be edited in this menu to fit the serial protocol requirements.

../../_images/sci.png

SCI Configuration

  • Baudrate: This specifies how fast data is sent over a serial line.

  • Length: This defines the number of data bits in each character: 4 to 8 bits.

  • Stop: Number of stop bits sent at the end of every character: 1, 1.5, 2.

  • Parity: Is a method of detecting errors in transmission. When parity is used with a serial port, an extra data bit is sent with each data character, arranged so that the number of 1 bits in each character, including the parity bit. Disabled, odd or even.

  • Use address mode: 9-bit data framing uses the bit typically associated with parity error detection to identify address messages. Sent serial data that does not have the address bit set will be ignored (unless the device had previously identified an address message associated with it). This option can be disabled or enabled.

Note

SCI A corresponds to port RS232 A, SCI B to port RS232 B and SCI C to port RS485.

CAN Setup

In this screen users can configure the baudrate and the reception mailboxes of each CAN Bus (CAN A or CAN B)

Since CEX is going to receive data on the CAN Bus, it is mandatory to configure a certain number of mailboxes to store that data until CEX reads it. A mailbox can be configured for multiple CAN message IDs as long as the mask is configured correctly and these messages are sent spaced out with enough time between them to allow the high priority core to read each one individually. More information on masks can be found in How to calculate a mask - FAQ section of this manual.

Warning

Since CEX PDI Builder allows up tp 32 mailboxes, users should make sure to leave at least one mailbox free for transmission (TX).

If any mailbox is full and another message arrives, the new message is discarded.

../../_images/can_setup.png

CAN Setup panel

More information about Mailboxes can be found in the Mailboxes section of the 1x PDI Builder user manual.